1. Field of the Invention
The present invention relates to an improvement of a magnetic coating composition used for preparing a magnetic recording medium.
2. Description of the Prior Arts
Magnetic coating compositions for a magnetic recording medium are classified into thermoplastic resin type compositions and thermosettable resin compositions.
A magnetic recording medium prepared by coating a magnetic coating composition obtained by using a thermosettable resin binder as at least one portion, on a substrate such as a polyester film, has advantages such as excellent smoothness of the surface and excellent gloss degree and high abrasive resistance. However, the thermosettable binder is crosslinked with a high reactive crosslinking agent, whereby it has serious disadvantages such as a short pot-life.
In order to overcome the difficulty, the inventors have studied the use of nitrocellulose, and thereby the desired results have been obtained.